ABSTRACT
@#Objective To develop and verify a sandwich ELISA method with bovine polyclonal antibody against rabbit polyclonal antibody for the determination of D antigen content of Sabin strain inactivated poliovirus vaccine(sIPV).Methods The rabbit polyclonal antibodies were prepared with sIPV vaccine bulks of type Ⅰ,Ⅱ and Ⅲ as antigens and detected for the titer and specificity by indirect ELISA.A double antibody sandwich ELISA with bovine polyclonal antibody as coating antibody and rabbit polyclonal antibody as detection antibody was developed to determine D antigen content,and the accuracy,precision and specificity to D antigen of the method were verified.sIPV vaccine samples from five domestic enterprises were detected by the developed method.Results The rabbit polyclonal antibodies for type Ⅰ,Ⅱ and Ⅲ sIPV with good specificity and high titer were prepared,and the double antibody sandwich ELISA method was successfully developed.Using four-parameter fitting,all three standard curves showed good linear relationship,and R~2 values were more than 0.99.The spike recoveries of type Ⅰ,Ⅱ and Ⅲ D antigens were all within 80%～120%,with average values of98.11%,97.41% and 98.66%,respectively.The CVs of repeatability and intermediate precision were all below 10%.The method also distinguished D antigens from C antigens.The developed method determined the D antigen contents of sIPV vaccines from five enterprises.Conclusion A sandwich ELISA method for determination of D antigen content in sIPV vaccine was successfully developed with satisfying accuracy,precision and certain D antigen specificity,which can be used to detect vaccines produced by different manufacturers.